Speaker



FIG. 1 is a front perspective view of a speaker;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a left side view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The elements depicted in broken lines in the various figures are included for environmental purposes only, and form no part of the claimed design. 

CLAIM The ornamental design for a speaker, substantially as shown and described. 